accel/tcg: Move can_do_io to CPUNegativeOffsetState

Minimize the displacement to can_do_io, since it may
be touched at the start of each TranslationBlock.
It fits into other padding within the substructure.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

7 files changed, 13 insertions, 11 deletions

diff --git a/accel/tcg/cpu-exec-common.c b/accel/tcg/cpu-exec-common.c
index 7e35d7f..82ae837 100644
--- a/accel/tcg/cpu-exec-common.c
+++ b/accel/tcg/cpu-exec-common.c
@@ -36,7 +36,7 @@ void cpu_loop_exit_noexc(CPUState *cpu)
 void cpu_loop_exit(CPUState *cpu)
 {
     /* Undo the setting in cpu_tb_exec.  */
-    cpu->can_do_io = 1;
+    cpu->neg.can_do_io = true;
     /* Undo any setting in generated code.  */
     qemu_plugin_disable_mem_helpers(cpu);
     siglongjmp(cpu->jmp_env, 1);
diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c
index 60f1986..de60fdb 100644
--- a/accel/tcg/cpu-exec.c
+++ b/accel/tcg/cpu-exec.c
@@ -455,7 +455,7 @@ cpu_tb_exec(CPUState *cpu, TranslationBlock *itb, int *tb_exit)
 
     qemu_thread_jit_execute();
     ret = tcg_qemu_tb_exec(env, tb_ptr);
-    cpu->can_do_io = 1;
+    cpu->neg.can_do_io = true;
     qemu_plugin_disable_mem_helpers(cpu);
     /*
      * TODO: Delay swapping back to the read-write region of the TB
diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c
index 3270f65..d69e046 100644
--- a/accel/tcg/cputlb.c
+++ b/accel/tcg/cputlb.c
@@ -1361,7 +1361,7 @@ io_prepare(hwaddr *out_offset, CPUArchState *env, hwaddr xlat,
     section = iotlb_to_section(cpu, xlat, attrs);
     mr_offset = (xlat & TARGET_PAGE_MASK) + addr;
     cpu->mem_io_pc = retaddr;
-    if (!cpu->can_do_io) {
+    if (!cpu->neg.can_do_io) {
         cpu_io_recompile(cpu, retaddr);
     }
 
diff --git a/accel/tcg/tcg-accel-ops-icount.c b/accel/tcg/tcg-accel-ops-icount.c
index 3d2cfbb..0af643b 100644
--- a/accel/tcg/tcg-accel-ops-icount.c
+++ b/accel/tcg/tcg-accel-ops-icount.c
@@ -153,7 +153,7 @@ void icount_handle_interrupt(CPUState *cpu, int mask)
 
     tcg_handle_interrupt(cpu, mask);
     if (qemu_cpu_is_self(cpu) &&
-        !cpu->can_do_io
+        !cpu->neg.can_do_io
         && (mask & ~old_mask) != 0) {
         cpu_abort(cpu, "Raised interrupt while not in I/O function");
     }
diff --git a/accel/tcg/tcg-accel-ops-mttcg.c b/accel/tcg/tcg-accel-ops-mttcg.c
index 4b0dfb4..ae95ba4 100644
--- a/accel/tcg/tcg-accel-ops-mttcg.c
+++ b/accel/tcg/tcg-accel-ops-mttcg.c
@@ -80,7 +80,7 @@ static void *mttcg_cpu_thread_fn(void *arg)
     qemu_thread_get_self(cpu->thread);
 
     cpu->thread_id = qemu_get_thread_id();
-    cpu->can_do_io = 1;
+    cpu->neg.can_do_io = true;
     current_cpu = cpu;
     cpu_thread_signal_created(cpu);
     qemu_guest_random_seed_thread_part2(cpu->random_seed);
diff --git a/accel/tcg/tcg-accel-ops-rr.c b/accel/tcg/tcg-accel-ops-rr.c
index 2d52328..671a3c4 100644
--- a/accel/tcg/tcg-accel-ops-rr.c
+++ b/accel/tcg/tcg-accel-ops-rr.c
@@ -192,7 +192,7 @@ static void *rr_cpu_thread_fn(void *arg)
     qemu_thread_get_self(cpu->thread);
 
     cpu->thread_id = qemu_get_thread_id();
-    cpu->can_do_io = 1;
+    cpu->neg.can_do_io = true;
     cpu_thread_signal_created(cpu);
     qemu_guest_random_seed_thread_part2(cpu->random_seed);
 
@@ -334,7 +334,7 @@ void rr_start_vcpu_thread(CPUState *cpu)
         cpu->thread = single_tcg_cpu_thread;
         cpu->halt_cond = single_tcg_halt_cond;
         cpu->thread_id = first_cpu->thread_id;
-        cpu->can_do_io = 1;
+        cpu->neg.can_do_io = 1;
         cpu->created = true;
     }
 }
diff --git a/accel/tcg/translator.c b/accel/tcg/translator.c
index b3e12d6..460bfc4 100644
--- a/accel/tcg/translator.c
+++ b/accel/tcg/translator.c
@@ -20,9 +20,11 @@ static void set_can_do_io(DisasContextBase *db, bool val)
 {
     if (db->saved_can_do_io != val) {
         db->saved_can_do_io = val;
-        tcg_gen_st_i32(tcg_constant_i32(val), cpu_env,
-                       offsetof(ArchCPU, parent_obj.can_do_io) -
-                       offsetof(ArchCPU, env));
+
+        QEMU_BUILD_BUG_ON(sizeof_field(CPUState, neg.can_do_io) != 1);
+        tcg_gen_st8_i32(tcg_constant_i32(val), cpu_env,
+                        offsetof(ArchCPU, parent_obj.neg.can_do_io) -
+                        offsetof(ArchCPU, env));
     }
 }
 
@@ -83,7 +85,7 @@ static TCGOp *gen_tb_start(DisasContextBase *db, uint32_t cflags)
     }
 
     /*
-     * cpu->can_do_io is set automatically here at the beginning of
+     * cpu->neg.can_do_io is set automatically here at the beginning of
      * each translation block.  The cost is minimal, plus it would be
      * very easy to forget doing it in the translator.
      */